nugging the tool .. other NC code .. relative movement

[djbeam]

I have looked and cannot see any reference to this .. so here goes.

I use several of the products from Vectric for the CNC Shark Pro Plus .. and by no means am I an expert in its use ..however I have come to conclude that machine setup is critical to allowing the machine to do its job.

One of the most frustrating thing is setting up the machine originally. There are JOG abilities but even the slowest one is much too course from proper alignment. Yes, you can turn power off and you can manually move the tool in fine increments in the X and Z direction .. but not Y .. So being an old programmer I thought, why can you not provide a field on your control software screen that displays the JOG parameter in the units that are currently set. This would allow you to use the current parameters of fast, med and slow (the resultant JOG parameter say in mills would be set when you hit the appropriate button and you would visually see it) but it would allow you to set this to something else .. as fine as the operator/machine can work in (say .001). This would be a God send .. I understand that the user can write simple G code to do this but what a pain and is fraught with possible errors .. sometimes expensive ones.

As well .. is there a G code operative in the NC programming that allows for relative movement from where the tool is currently .. not just the absolute XYZ co-ordinates .. example if the tool is at x=.2, y=.3 and z=.4, is there an instruction that would allow you to move the Y by +.05 .. which would be the same as y=.35.

Don

[jeb2cav]

Hi Don,

Next Wave Automation has indicated that they are going to provide 'better' jog controls with their next software release in other posts. I think this will address the first part of your post. I agree that setting up the job is critical.

I can't speak to the g-code question, sorry.

[fison]

Yes there is a way to move relative to the current position in G-Code but you still have create and upload a file. Before you send the move commands you have to set either of the two settings shown below:

G90 is Absolute Distance Mode
G91 is Incremental Distance Mode

If you're using Mach3 you should be able to send commands interactively but I've never been able to get it to work with my Shark.

Here's a link to a G-Code reference:

http://linuxcnc.org/docs/html/gcode.html